3-5 reading acyclic parameters, 3-5 reading acyclic parameters -7 – Yokogawa DO202 2-Wire Dissolved Oxygen Analyzer User Manual

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Profibus 4-7

IM 12A00A01-61E

Beforehandone must configure which information will be exchanged.
According with the Profibus-PA Profile 3.01, there are two kinds of configurations possible. The Identifier
byte (or short identifier) and the Extended Identifier Format (or long identifier). The EXA supports both kinds
of configurations. The user can choose either “Analog Input (short)” or “Analog Input (long)” and will end up
with the same result.

The function blocks of the EXA are in a specific order. The configuration of the cyclic data should be done
in the same order.

For the EXA. the process values are mapped as follows:

PH202

SC202

ISC202

DO202

slot (1)

“AI1”

pH

SC1

SC1

Dissolved Oxygen

slot (2)

“AI2”

Temperature

Temperature

Temperature

Temperature

slot (3)

“AI3”

ORP/rH

SC2

SC2

Percent Saturation

The GSD file of the EXA 202 specifies 3 modules:

;Empty module
Module = “Empty Module” 0x00
1
EndModule
;Modules for Analog Input
Module = “Analog Input (AI)short” 0x94
2
EndModule
;Modules for Analog Input
Module = “Analog Input (AI)long” 0x42,0x84,0x81,0x81
3
EndModule

;--- Description of the module assignment: ---
;
SlotDefinition
Slot(1) = “AI1” 3

1,2,3

Slot(2) = “AI2” 3

1,2,3

Slot(3) = “AI3” 3

1,2,3

Examples:
- Configuring the output of the AI block 1 (pH) and the output of AI block 2 (temperature):

“Analog Input (short) “ and “Analog Input (short) “ and “Empty Module” or “0x94, 0x94, 0x00”

- Configuring the output of AI block 1 (pH) only:

“Analog Input (long) “ and “Empty module” and “Empty module” or “0x42, 0x84, 0x81, 0x81, 0x00, 0x00”

Note:

Most Master Class 1 devices have an advanced Human Machine Interface and will guide you through
these configurations.

4-3-5 Reading acyclic parameters

Communications occur on a peer-to-peer basis. A cyclic communication services for parametrization, opera-
tion, monitoring, alarm/error handling and diagnostics of intelligent devices may be handled in parallel to
cyclic transfer.

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